Soil Nutrients By:

Objectives Know the definition of deficiency, nutrient, toxicity, macronutrient, micronutrient. Identify the plant deficiencies from pictures Evaluate a plant to identify the nutrient absorption rate.

Terms and Definitions Nutrient – Element necessary for plant growth and reproduction. Deficiency – Plant condition where an essential nutrient is not sufficiently available. Micronutrient – Nutrient needed in smaller quantities

Terms and Definitions Macronutrient – Nutrient needed in larger quantities Toxicity – A point that is reached where too much of a nutrient becomes poisonous

Primary and Secondary Nurtrients Nitrogen Phosphorus Potassium Calcium Magnesium Sulfur

Nitrogen Functions Gives plants the green coloring Makes up 1% to 4% of plant’s harvested material Induces vigorous, rapid growth in plants 98% of the planet’s nitrogen is in the primary rock of the Earth, the remaining 2% is in the atmosphere Most readily absorbed Crops absorbed more nitrogen from the soil than any other nutrient. Most frequently the limiting factor in crop production.

Nitrogen Deficiency Symptoms Chlorosis – Yellowing in color of leaves Plant growth is stunted

Phosphorus Stimulates root growth Important for plant cells genetic material and energy transfer with ATP 3rd most readily absorbed Available in soil as an orthophosphate ion (H2PO4 and HPO4) – Important because these ions react easily with other compounds to become less available

Phosphorus Deficiency Symptoms Stunted Growth Purplish coloring of leaves

Potassium Production and translocation of carbohydrates Water intake and respiration Stiffens stalks and straws 2nd most readily absorbed

Potassium Deficiency Symptoms Shorter and weaker plants Bronzing or a browning of leaf color

Magnesium Vital for photosynthesis Chlorophyll or the green coloring of the plant Needed for protein synthesis

Magnesium Deficiency Symptoms Leaves curl along the margins Leaf parts show a whitish color

Calcium Gives plant strength Stimulates formation of nitrates Promotes root and leaf growth

Calcium Deficiency Symptoms Chlorosis beginning in the leaf edges and moving inward Terminal buds become distorted

Sulfur Stimulates seed production Necessary for nodule formation on legumes Affects protein and crop quality

Sulfur Deficiency Symptoms Similar symptoms to that of a nitrogen deficiency Stunted appearance

Micronutrients in Plants Iron Maganese Boron Molybdenum Copper Zinc Chlorine

References Laca, Andrew. “Ag Lesson Plans in Power Point”. Soil Furtility. 19 May 2001. Glen Rose FFA, Glen Rose., USA. 27 Feb 2005 <http://www.glenroseffa.org/lesson%20plans.htm> Primal Seeds. 26 Oct 2002. 27 Feb 2005 <http://www.primalseeds.org/nutrients> Nutrient Deficiency Symptoms on Agronomic Crops. 12 June 2002. 27 Feb 2005 <http://www.nrs.mcgill.ca/whalen/nutrient/symptom.html>